Sunnybrook Health Sciences Centre

About: Sunnybrook Health Sciences Centre is a healthcare organization based out in Toronto, Ontario, Canada. It is known for research contribution in the topics: Population & Medicine. The organization has 7689 authors who have published 15236 publications receiving 523019 citations. The organization is also known as: Sunnybrook.

MR imaging of entrapment neuropathies of the lower extremity. Part 2. The knee, leg, ankle, and foot.

Abstract: Entrapment neuropathies of the knee, leg, ankle, and foot are often underdiagnosed, as the results of clinical examination and electrophysiologic evaluation are not always reliable. The causes of most entrapment neuropathies in the lower extremity may be divided into two major categories: (a) mechanical causes, which occur at fibrous or fibro-osseous tunnels, and (b) dynamic causes related to nerve injury during specific limb positioning. Magnetic resonance (MR) imaging, including high-resolution MR neurography, allows detailed evaluation of the course and morphology of peripheral nerves, as well as accurate delineation of surrounding soft-tissue and osseous structures that may contribute to nerve entrapment. Familiarity with the normal MR imaging anatomy of the nerves in the knee, leg, ankle, and foot is essential for accurate assessment of the presence of peripheral entrapment syndromes. Common entrapment neuropathies in the knee, leg, ankle, and foot include those of the common peroneal nerve, deep peroneal nerve, superficial peroneal nerve, tibial nerve and its branches, and sural nerve.

Criteria for analysis of multicomponent tissue T2 relaxation data

Abstract: Monte Carlo simulations were performed to determine whether the multicomponent T2 distribution of tissue can be estimated accurately from T2 decay data acquired in vivo. Simulated data were generated for white matter, fast twitch muscle, and breast tissue. The signal-to-noise ratio, number of data samples, and minimum echo time were varied from the experimental conditions currently achievable with MRI to those achievable for in vitro experiments. Data were fitted by a distribution of T2 values using the T2NNLS algorithm, and statistics characterizing the estimated T2 components were determined. Current MRI techniques were found to provide conditions insufficient for accurate multicomponent T2 analysis on a pixel-by-pixel basis. However, volume localization methods that measure T2 decay from a large volume of interest have potential for this analysis. These results illustrate a general framework for development of new techniques to measure T2 decay accurately in vivo.

Duration of analgesic effectiveness after the posterior and lateral transversus abdominis plane block techniques for transverse lower abdominal incisions: a meta-analysis

Abstract: Background Both posterior and lateral transversus abdominis plane (TAP) block techniques provide effective early (0–12 h) postoperative analgesia after transverse incision surgery. However, whether either technique produces prolonged analgesia lasting beyond 12 h remains controversial. This meta-analysis examines the duration of analgesia associated with posterior and lateral TAP blocks in the first 48 h after lower abdominal transverse incision surgery. Methods We retrieved randomized controlled trials (RCTs) investigating the analgesic effects of TAP block compared with control in patients undergoing lower abdominal transverse incision surgery. Outcomes sought included interval postoperative i.v. morphine consumption and also rest and dynamic pain scores at 12, 24, 36, and 48 h postoperatively. Opioid-related side-effects and patient satisfaction at 24 and 48 h were also assessed. The 12–24 h interval morphine consumption was designated as a primary outcome. Results Twelve RCTs including 641 patients were analysed. Four trials examined the posterior technique and eight assessed the lateral technique. Compared with control, the posterior TAP block reduced postoperative morphine consumption during the 12–24 h and 24–48 h intervals by 9.1 mg (95% CI: −16.83, −1.45; P=0.02) and 5 mg (95% CI: −9.54, −0.52; P=0.03), respectively. It also reduced rest pain scores at 24, 36, and 48 h, and also dynamic pain scores at 12, 24, 36, and 48 h. Differences were not significant with the lateral TAP block. Conclusion Based on the comparisons with control, the posterior TAP block appears to produce more prolonged analgesia than the lateral TAP block. Future RCTs comparing these two techniques are required to confirm our findings.

Impact of patient and target-vessel characteristics on arterial and venous bypass graft patency: insight from a randomized trial.

Abstract: Background— The purpose of this investigation was to determine optimal patient and target-vessel characteristics to maximize arterial and venous graft patency on the basis of data from a large clinical trial. Methods and Results— Angiographic data on 440 radial artery grafts and 440 saphenous vein grafts were analyzed with methodology to account for within-patient clustering. Multivariable models that incorporated patient demographic, operative, anatomic, and postdischarge medical management were constructed to determine predictors of graft occlusion. Radial artery use was strongly protective against graft occlusion at 1 year after adjustment for all covariates, with a larger protective effect seen in women (P=0.05 for a subgroup-by-treatment interaction). Among all grafts, diabetes and small target-vessel diameter were associated with an increased risk of graft occlusion, and grafting to a target vessel with more severe proximal stenosis was associated with a decreased risk of graft occlusion. With regar...